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BlueRaja - Danny Pflughoeft
  • Member for 11 years, 7 months
  • Last seen this week
36 votes
7 answers
71k views

Why is gravitational potential energy negative, and what does that mean?

45 votes
6 answers
13k views

Does alternating current (AC) require a complete circuit?

45 votes
5 answers
9k views

Have we figured out how to analyze turbulent fluids?

17 votes
4 answers
7k views

Can an object accelerate to infinite speed in a finite time-interval in non-relativistic Newtonian mechanics?

3 votes
4 answers
2k views

Intuitive explanation for why time symmetry implies conservation of energy?

6 votes
3 answers
290 views

Why doesn't finite field propagation speed contradict Gauss's law? [duplicate]

13 votes
4 answers
258 views

If different light frequencies travel at different speeds in air, why doesn't the sun have a rainbow halo?

1 vote
2 answers
143 views

If spacetime is expanding, shouldn't lengths expand at an equal rate? [duplicate]

1 vote
1 answer
129 views

Does someone falling into a black hole see the outside universe moving faster?

3 votes
1 answer
126 views

How do we know the distance between stars (without assuming flat spacetime)?